diff --git a/app/requirements.txt b/app/requirements.txt
index b57e45c..4743c50 100644
--- a/app/requirements.txt
+++ b/app/requirements.txt
@@ -6,3 +6,4 @@ flask-wtf>=0.14
 python-dotenv>=0.6.2
 gunicorn>=19.6.0
 flask-analytics>=0.6.0
+wtforms>=3.0.0a1 # not directly required, pinned by Snyk to avoid a vulnerability